Optical brightening agents of the 4, 4&#39;-bis-(triazinylamino)-stilbene disulfonic acid series



hired States ire 3,051,704 OPTICAL BRIGHTENING AGENTS {BF Tim 4,4- BiS-(TRIAZlNYLAD/lllN)-STILBENE DISULFON- 1C ACID SERES Robert Gehm, Oswald Schmidt, Heinrich Mertens, Wolfgang Grunwald, and Manfred Hehl, all of Ludwigshafen (Rhine), Germany, assignors to Badische Anilin- & Soda-Fabrik Ahtiengesellschaft, Ludwigshafen (Rhine), Germany No Drawing. Filed .l'an. 19, 1966, Ser. No. 3,265 Claims priority, application Germany .ian. 24, 1959 3 Claims. (Cl. 260-240) This invention relates to novel optical brightening agents and to a process for their production.

More particularly, the invention relates to optical brightening agents which are derivatives of 4,4'-bis-(tri azinylamino)-stilbene disulfonic acid and which are water-soluble compounds of the formula in which X stands for a substituent selected from the group consisting of CHPCH:

0 8 N \CHPCIEH/ CHr H and CHq-CH:

M stands for a cation,

It is known that certain derivatives of 4,4'-bis-(triazinylamino)-stilbene disulfonic acid are optical brightening agents which may be used for brightening textiles, paper and other materials. Unfortunately, the fluores cent power of these substances is severely impaired when the materials to be brightened are additionally treated with precondensates of thermosetting resins which are applied in textile finishing, for example N,N-dimethylol- 4,5-dihydroxy imidazol-Z-one.

It is an object of the present invention to provide new optical brightening agents, the fluorescent power of which is practically unimpaired by precondensates of thermosetting resins.

A further object of this invention is to provide optical brightening agents which exhibit the aforesaid properties and are moreover distinguished by good fastness to light and washing and a high degree of fluorescent or brightening power.

The new compounds of this invention are useful optical brightening agents and may be components of optical brightening compositions of all kinds, as for example bleaching baths, washing agents, brightening baths, iwashing liquors, paper pulps and the like. As a rule, the said new optical brightening agents are used in an aqueous medium as free sulfonic acids or in the form of watersoluble sulfonates, such as alkali metal sulfonates, as for example SOdilUn and potassium sulfonate, ammonium sulfonate or sulfonic acid salts of organic bases, as for example the sulfonic acid salts of primary, secondary or tertiary amines. The optically brightened materials should preferably contain from 0.5 to 5% of the new optical brightening agents with reference to the weight of the said materials.

The mixtures described are suitable for the optical brightening of structures of all kinds both on the surface and in the mass, for example foils, films, felts, or textile materials, such as fibers, threads, flocks, woven or nonwoven fabrics, of natural, regenerated and synthetic material, such as for example leather, synthetic polymers (plastics), and paper. Especially good effects are obtained in the optical brightening of structures of native or regenerated cellulose or linear polyamides.

A particular advantage of the new brightening agents in the fact that optical brightening compositions and brightened products containing the said brightening substances can be used in bleaching fibrous materials even under extreme conditions, for example cotton yarn in the form of cross-wound bobbins, with hydrogen peroxide in so-called high-temperature apparatus at temperatures above C. for example at to C. Since their absorptive capacity, in contrast to the optical brightening agents hitherto known, is practically unimpaired by temperature of 110 to 120 C., the above-mentioned derivatives of 4,4'-diaminostilbene can be added directly to the baths used for bleaching.

The new brightening agents of the above Formula I can be prepared by various methods. For example, two mols of a cyanuric acid halide may be reacted with 1 mol of an alkali metal salt of a 4,4'-diamino-stilbene disulfonic acid of the general formula CH=CH NH:

SO H S0 11 V and then with two mols of a compound having the formula CHrCHg 02S NH GHQ-CH1 v1 GHg- H 02S NH CED-(3H 0H3 VII The halogen atoms in the molecules of the resulting products Which can also be obtained when two mols of a cyanuric acid halide are first reacted with two mols of 1,1-thiamorpholine dioxide or 2,6-dimethyl-l,l-thiamorpholine dioxide and the reaction product is further reacted with .an alkali salt of a 4,4-diaminostilbene disulfonic acid of the general Formula V are then replaced by reacting these products with aqueous alkali, ammonia, suitable primary or secondary alkyl, cycloalkyl, hydroxyalkyl, alkoxyalkyl, aryl or heterocyclic amines or by reacting the said products with formaldehyde and 1,1-thiamorpholine dioxide.

1,1-thiamorpholine dioxide and 2,'6-dimethyl-1,1-thiamorpholine dioxide can be prepared according to the Na S process described in the copending patent application Serial No. 828, 048, filed July'20, 1959, by Robert Gehm and Johannes Dehnert.

The above-mentioned reaction of cyanuric acid halides, for example cyanuric acid chloride, with an alkali metal salt of a 4,4'-diaminostilbene disulfonic acid and the said 1,1-thiamorpholine dioxide derivatives is preferably carried out in aqueous or organic liquids. Inert solvents and/ or diluents may be used for this purpose, particularly those which are miscible with water, as for example acetone, dioxane, dimethylformamide or N-methyl pyrrolidone alone, either in admixture with each other or with water. The hydrohalic acid, for example hydrochloric acid evolved during this reaction is neutralized for example by adding an alkaline reagent such as sodium bicarbonate, sodium carbonate or a dilute aqueous solution of sodium or potassium hydroxide. Low reaction temperatures, for example a temperature between and +10 C., are preferred during the first reaction step, i.e., when the cyanuric acid halides are combined with the diaminostilbene disulfonic acids of Formula V.

When the 1,1-thiamorpholine dioxide derivatives of Formula VI or VII are introduced into the reaction mixture, the reaction temperature is slightly raised to for example +10 to +40 C. During the third reaction step, i.e., when the reaction products are further reacted with aqueous alkali, ammonia, the amines mentioned above or with mixtures of formaldehyde .and 1,1-thiamorpholine dioxide, the reaction temperature is raised to still higher values, for example to +60 to 200 C.

The alkali metal'salts, the ammonium salts, and the salts of the organic bases named above of the compounds of Formula I are prepared in known manner by using the optical brightening agents of Formula I in the form of their free sulfonic acids.

Procedures illustrating the production of the new optical brightening agents are given in Examples 1 and 7 of this specification.

The following examples will further illustrate this in- Vention, but the invention is not restricted to these examples. The parts and percentages specified in the examples are by weight.

Example 1 Preliminarily cleansed cotton yarn in the form of cross-wound bobbins is treated for an hour at a temperature of 115 to 120 C. in a closed apparatus suitable for temperatures above 100 C. at a liquor ratio of 10:1 in an aqueous bath containing in each liter 2 cos. of 40% hydrogen peroxide, 1 gram of sodium hydroxide, 4 cos. of a 50% aqueous sodium silicate solution, 0.5 gram of crystallized magnesium sulfate (MgSO .7H O) and 0.01 to 0.05 gram of the 4,4-diarninosti1bene derivative of the formula SO Na VIII The material is then rinsed and dried. An optically brightened cotton yarn is obtained having a strong and brilliant whitening effect.

The compound of the Formula VIII can be prepared in the following way:

(a) A solution of 37 parts of cyanuric acid chloride in 240 parts of acetone is allowed to flow slowly while cooling into a mixture of 400 parts of ice and 400 parts of Water. Into this mixture there is then introduced at to -|-5 C. a solution of 27 parts of 1,1-thiam0rpholine dioxide and 10.6 parts of sodium carbonate in 400 parts of water and the reaction mixture stirred for half an hour at this temperature. Then it is filtered by suction, washed with ice water and there are obtained 50 parts of N-(2,4-dichlor-1,3,5-triazinyl)-1,1-thiomorpholine dioxide, which after recrystallization from ethanol gitgurs in the form of white needles of the melting point (b) Into a mixture of 94 parts of the intermediate product described under (a) with 1500 parts of acetone there is introduced at -25 C. a solution of 64 parts of 4,4-diaminostilbene-2,2'-disu1fonic acid and 27 parts of sodium hydroxide in 1500 parts of water. The reaction mixture is further stirred for another 3 hours at +25 C. The deposited product is then filtered off by suction and dried. 82 parts of the reaction product are obtained. A further 5 0 parts are recovered from the mother liquor.

(c) parts of the product described under (b) and 31 parts of ethanolamine are boiled in 300 parts of water for 3 hours under reflux. The compound of the Formula VII is obtained in a very good yield.

For the production of the compound of the Formula VIII it is not necessary to isolate the intermediate products. It is possible, in a Way similar to the known methods for the production of derivatives of 4,4'-diaminostilbene, first to react the diaminostilbene disulfonic acid with cyanuric acid chloride and then to exchange the reactive chlorine atoms remaining on the triaz ine rings for the radicals of 1,1-thiamorpholine dioxide and ethanolamine.

Example 2 Preliminarily bleached cotton fabric is treated for an hour at a liquor ratio of 50:1 in an aqueous bath containing in each liter 0.01 to 0.05 gram of the 4,4"- diaminostilbene derivative of the formula 3 grams of sodium dithionite and 2 grams of sodium carbonate (anhydrous) and then dried. A fabric is obtained which exhibits an excellent whitening efiect of good fastness to light and washing.

6 Example 5 Fabric of polycaprolactam is kept in motion for minutes at a liquor ratio of 50:1 at 70 C. in an aqueous bath containing per liter 0.05 to 0.1 gram of the 4,4-

Instead of the compound IX, there may be used with 5 diaminostilbene derivative of the formula NaOzS similar results the corresponding amount of the 4,4'-diamino-stilbene derivative of the formula Example 3 SOsNa XIII and 2% of 85% formic acidwith reference to the weight 15 of the fabric. The textile material thus treated is dis- IIIXCzHaOH):

tinguished from untreated fabric of the same kind by an excellent degree of whiteness of excellent fastness to light.

Example 6 Yellowish white paper is treated with an aqueous solution which contains per liter 0.07 to 0.5 gram of the 4,4-

tains P liter 5 to 10 grams of the resultant IniXfllfe, a diaminostilbene derivative of Formula VIII described in pure White, optically brightened washed material is obtained.

The brightening eifect is also very good when the compound of the Formula IX is replaced by the corresponding amount of the 4,4'-diaminostilbene derivative of the formula Example 4 terial is then treated for 10 to 20 minutes at 40 C. in

an aqueous bath which contains per liter about 0.01 gram of the 4,4'-diaminostilbene derivative of the formula at a liquor ratio of 20:1 to 50:1. A very well optically weight of fabric.

brightened washed material is thus obtained.

If the compound of the Formula XII be replaced by the corresponding amount of the 4,4'-diaminostilbene derivative of the Formula X[ specified in Example 3, the brightening eifect obtained therewith is also very good.

Example 1. The paper is then rinsed and dried. A marked brightening effect of very good fastness to light is achieved thereby.

The same effect can also be achieved by adding 0.1 to

1 gram per liter of the same compound to the usual paper pulp.

TM a):

OaNa Example 7 Preliminarily washed fabric of polycaprolactam is treated at 70 C. for 20 minutes at a liquor ratio of 50:1 in an aqueous bath which contains per liter 0.05 to 0.1 gram of the 4,4'-diaminostilbene derivative of the formula SO Na XIV and 2% of formic acid (85%) with reference to the XII The textile material thus treated is distinguished from untreated fabric of the same kind by a considerably improved whiteness effect of good fastness to light. A similar effect is obtained by using the corresponding triethanolamine salt.

7 8 The compound of the Formula XW can be obtained in the following way: 7 T z 20 parts of the compound of the formula (IJHa CH CH CH CH GHQ-CH UHF-CH2 IITH: IIIHI 10 CH: C-N' N-C GET-CH4 CHz-CH: N CHN no=on1sn-o N ois N- mo N-- 0= N=o \cm-om CHr-Ofia 03H 303E I NH: NH: /OH2CE2 One N- @NH- OH2-GH2 CHr-CE: 02s /N HO obtainable in known manner are dissolved in 300 parts of 2 N aqueous sodium hydroxide solution. Into this solution there are introduced 15 paits of 1,1-thiamorpholine Example 9 dioxide. Then 11 parts of a 30% aqueous formaldehyde 0 solution is allowed to flow in slowly and the mixture is A PIEVIOUSIY Washed P Y P f K 1S fiieated heated f 7 hours at 70 C h compound f h at a liquor ratlo of 50:1 at 90 C. for 20 minutes in an mula XIV is separated in the form of the free sulfonic aqueous bath h fi cPntains per 5? 1 g' gram h hl D of the optical brig temng agent spec e int e st paraa id by addition of dilute aqueous Ydroc or1c acid g p of EX P 8 and the P of which has been Example 8 justed to 4.5 by adding 85% formic acid. After drying,

, the fabric shows a considerably improved degree of white- Previously bleached cotton fabric is treated at C. ness as compared with an untreated fabric of the same for 20 minutes in a bath containing per liter 0.05 to 0.1 kind. gram of the compound of the formula 35 Instead of the optical brightening substances of the O: 02 CH3 CH2 C (RH; 52 H2 $112 OH;

om-on, N N omog, 02s N-L J-HN CH=OH NH-k N so, Y N

OHz-OH: GHQ-0H2 SO Na SO Na ata liquor ratio of :1 using water of 214.8 U.S. defirst paragraph of Example 8 there may be used the comgrees of hardness. V 50 pounds of the table given in the third paragraph of Ex- After drying, the cotton fabric thus treated is distinample 8. guished from untreated fabric of the same kind by a 0011- Example 10 siderably improved whiteness effect.

A similar brightening effect is obtained by using, instead of the brightening compound of the first paragraph A previously bleached cotton fabric is impregnated with an aqueous solution containing per liter 1 gram of the optical brightening agent described in the first paraof this example, the compounds of the following table: graph of Example and grams of ,N,N' dimethy101 4,S-dihydroxy-imidazol-Z-one, and 15 grams of magnesiz Z um chloride, squeezed OE and dried at C. The dry A 60 impregnated fabric is then treated for 5 minutes with N r N N hot air at C. so that condensation takes place. The

I I fabric thus finished shows a considerably improved de- T J-HN OH=OHNH T gree of whiteness as compared with a cotton fabric which I has been finished in the same manner except that instead SOaNa S03Na 65 of the abovementioned optical brightening agent the compound of the formula,

SO Na SO Na (an optical brightening agent of the prior art) has been used.

Example 1] N1? NN' l l SO Na SOaNa The fluorescent power of the samples is then measured by means of a Fluorometer as manufactured by Dr. B. Lange, Berlin. The method of measuring is described by H. J6rder in Melliand Textilberichte, vol. 40 (1959), pages 1190 to 1194. As the control there is used a sample of the same but untreated polycaprolactam fabric. The galvanometer is set in such a way that the reading from the control sample is and only the dif- CH OH CHPCHZ ference between the fluorescent intensities of the samples treated with the optical brightening agents on the one 10 We claim:

1. A water-soluble compound of the formula YL HN-QOEQHQNH-L Y s03 M soa M in which X stands for a substituent selected from the group consisting of GHQ-0H2 and CHr-CH:

02S N-CHr-NH- M is a cation and Y is a substituent selected from the group consisting of hydroxy, amino, dimethylamino, 2- hydroxyethylamino, di-(2-hydroxyethyl)-amino, 3-methoxypropylamino, phenylamino, pyrrolino, morpholino and the radical of the formula CHrCHg CH -CH: 2. A water-soluble compound of the formula NH-OHrCHg-OH CHg-C z so3 M so3 M wherein M is an alkali metal cation.

3. A water-soluble compound of the formula hand and the control sample on the other hand is measured. The following table shows the scale readings.

Sample: Scale reading A 3 8.5 B 33.5 C 3 1 .0 Control 0 It can be seen that the sample treated with the optical brightening agent according to this invention (A) has a considerably higher fluorescent intensity than the other samples.

SOa M SO3 M 5 wherein M is an alkali metal cation.

References Cited in the file of this patent UNITED STATES PATENTS 2,618,636 Williams et al. Nov. 18, 1952 2,658,065 Wallace et a1. Nov. 3, 1953 2,666,052 Williams et a1 Jan. 12, 1954 FOREIGN PATENTS 152,928 Australia Aug. 24, 1949 OTHER REFERENCES Elder-field: Heterocyclic Compounds, volume 5, pages 5 612 to 616, John Wiley and Sons (1957).

UNITED STATES PATENT OFFICE, CERTIFICATE C0 ECTION Robert Gehm et a1,

It is hereby certified that error ap ent req'liring correction and that the sai corrected below.

pears in the above numbered patd Letters Patent should read as Column 10, line 39 for "pyrrolino read pyrrolidino Signed and sealed this 23rd day of June 1964c (SEAL) Attest:

ERNEST W; SWIDER EDWARD J. BRENNER Aitesting Officer Commissioner of Patents 

1. A WATER-SOLUBLE COMPOUND OF THE FORMULA 